A four bar mechanism is shown in the figure. The link numbers

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A four bar mechanism is shown in the figure. The link numbers are mentioned near the links. Input link 2 is rotating anticlockwise with a constant angular speed ω₂. Length of different links are
O₂O₄ = O₂ A = L,
AB = O₄ B = 2 L
The magnitude of the angular speed of the output link 4 is ω₄ at the instant when link 2 makes an angle of 90° with O₂O₄ as shown. The ratio
ω₄ is
ω₂

_____ (round off to two decimal places).

1. 0.79
2. 0.88
3. 0.25
4. 0.99

Correct Option: A

Now, O₄C = cos 75°
O₄C = sin 75°
∆AO₂I₂₄ ≈ ∆BI₂₄C

	L	=	√2Lsin75°
	x		x + L + √2cos75°

⇒	L	= 0.2679
	x

	ω₄	=	1	= 0.7887 ≈ 0.79
	ω₂		1 + 0.267